Item identifiers comprise visibly detectable unique image information, such as bar codes, encoded areas at the periphery of or incorporated into the image itself, and non-encoded yet unique image components which serve to identify or categorize an item or image subject. The information can be extracted automatically, for example by an optical scanner, or can be read or otherwise detected by a user. Independently-created item identifiers are employed by retailers to identify, track, and manage inventory items. If entered into a database, the item identifier can be cross-referenced to other relevant item information such as pricing, inventory, purchase terms, etc.
Barcodes are a ubiquitous form of item identifier. With the adoption of UPC as the standard for retail grocery stores in the late 1970's, barcodes have become a fast, easy, and accurate data entry method. A barcode encodes information related to an item with which the barcode is associated. Typically, a barcode is associated with an item by affixing the coded pattern of the barcode to the item or to the item's packaging. In order to use a barcode associated with an item, a retailer first extracts encoded information from the barcode using a barcode scanner. The extracted information may consist of an identification code such as a Stock Keeping Unit (SKU). Of course, instead of scanning the barcode, the identification code which may be printed beneath the barcode itself may be manually read and entered into a device via a keyboard. In either case, the detected code may then be used to retrieve a retail price of the item from a database, to update a location of the item in a database, to obtain warranty or other information regarding the item from a database, etc.
In view of the prevalence and usefulness of barcodes, many devices for extracting information from them have been developed for use by retailers and consumers. These devices include grocery checkout scanners, handheld scanners, and scanning pens. Peripheral modules capable of decoding barcodes are also being developed for devices such as Personal Digital Assistants (PDAs) and mobile telephones. Some of these devices are capable of extracting information from barcodes of several different formats. One system, the Cue Cat™ system by Digital:Convergence, operates by scanning a pen across a barcode from a product or advertisement to extract the code and then causing a World Wide Web (“Web”) browser to access a Web page related to the product or advertisement. In view of the number and diversity of available barcode-decoding devices, the development and purchase of these devices represents a substantial capital investment by manufacturers and consumers alike.
Most of the conventional devices make use of laser based technology for reading the barcodes. A basic barcode reader consists of a laser scanner and a decoder, with a cable to interface the decoder to the computer or terminal. In operation, the scanner scans a barcode pattern and produces an electrical output that corresponds to the bars and spaces in the scanned pattern. A decoder then takes the digitized bar space patterns, decodes them to the correct data, and transmits the data to the computer over a wired or wireless connection, immediately or on a batch basis. Most laser based barcode readers have high power consumption due to the power requirements of the laser system in the scanner. Such power consumption requirements are an impediment to using laser-based barcode readers in small, low-powered devices, such as personal data assistants (PDAS) or cellular phones. Moreover, the use of the scanning devices has been, to date, limited to reading barcodes only and not to making use of the read/extracted information.
Existing technology for the use of extracted item identifiers and the associated item information has been detailed in U.S. patent application Ser. No. 09/847,779, filed on May 2, 2001 and entitled “SYSTEM TO INTERPRET ITEM IDENTIFIERS” (YOR92001-0118). Therein a digital camera is used to capture an image of an item identifier and to transmit the image to a central server. In response to the transmission, item information is received from a central server. For transmission of image information, which are traditionally large files, image compression mechanisms have been developed, such as JPEG, TIFF, and GIF. The following reference describes examples of the state of the prior art: Encyclopedia of Graphics File Formats, Second Edition, J. D. Murray and W. VanRypers, O'Reilly & Associates, Inc., California, 1996.
The output of a digital camera is typically a JPEG-compressed color image. JPEG, one of the leading industrial image compression mechanisms, was designed for compressing either full-color or gray-scale images of natural, real-world scenes. JPEG is specially adapted for photographs, naturalistic artwork, and similar material, but does not give best results for lettering, simple cartoons, or line drawings. The JPEG compression process is “lossy,” meaning that the decompressed image isn't quite the same as the original image. (There are lossless image compression algorithms, but JPEG achieves much greater compression than is possible with lossless compression methods.) JPEG is designed to exploit known limitations of the human eye, notably the fact that small color changes are perceived less accurately than are small changes in brightness. Thus, for compressing images that will be looked at by humans, such as the ones captured by a digital camera, JPEG is one of the most used standards for compressing the digital images.
One useful property of JPEG is the ability to vary the degree of lossiness by adjusting the compression parameters. Accordingly, an image creator can balance file size against output image quality, for example generating very small files when low image quality is acceptable as it is when indexing image archives. Conversely, if a better output quality is desired, the compression can be tailored to increase the output image quality to a satisfactory level.
Yet another aspect of image extraction, whether of an independently-created item identifier which is added to the image or of an item identifier comprising image content information, is the preference to allow a user to identify which image information is of interest as the item identifier for further treatment, whether it be further viewing, image transmission, or image processing. For mobile commerce, images have become an integral part of the communications; however, not all of the information contained in every image is of interest for the execution of mobile applications and/or for the sharing of information among users (i.e., shared image presentation in, for example, video-conferencing applications). Since most image compression techniques are not tailored to application-specific requirements, those techniques are often not useful for mobile commerce applications. What is needed is a way for users of mobile devices to indicate which portions of an image are item identifiers which are of interest to the application, thereby allowing selective processing (e.g., compression) and, a way to prioritize scarce bandwidth resources to support the transmission of necessary image data.
Another problem with mobile imaging devices is that the existing bandwidth is rarely sufficient to transmit the full quality images captured by standard digital cameras. Such images, uncompressed, can reach 2 MBs in size and can still be 200 KB when compressed. Even with a commonly available cellular communications connection of 9600 bits/second performing a successful, error free transmission, would still require ˜176 seconds to transmit a 200 KB photo image. Prior art methods for selective reduction of video data include U.S. Pat. No. 6,356,664 entitled “SELECTIVE REDUCTION OF VIDEO DATA USING VARIABLE SAMPLING RATES BASED ON IMPORTANCE WITHIN THE IMAGE,” wherein regions are selectively reduced using variable rate sampling. However, the prior method is not user interactive and does not remove or segment image data.
It is desirable, therefore, and an object of the present invention, to provide a system and method for extracting selected image information as item identifiers for selective image handling.
It is another object of the invention to provide automatic item identifier extraction whereby embedded image information can be extracted by low cost, low power consumption means prior to JPEG compression and transmission.
Yet another object of the invention is to provide a system and method whereby a user can designate an image area of interest within an image as an item identifier for further treatment.